Police and volunteer lifeguards at Auckland’s Muriwai Beach are warning beachgoers to be aware of quickly rising tides after two young girls became stranded on the rocks.

A police spokesperson said they were alerted about 5.20pm yesterday after a boy and the two girls walked around the rocks to the left of Muriwai Beach to collect mussels and got trapped.

Auckland Maritime Unit Senior Sergeant Garry Larsen said the group carried out the walk at low tide and thought they had time to collect and return, but were caught in a small cave by the incoming tide.

“The boy made it back to the beach and raised the alarm,” he said.

“The Police Eagle helicopter quickly spotted the two girls and directed the surf lifeguards to their location where they were able to assist the duo out along the rocks and back to safety.

Police and Muriwai Volunteer Lifeguard Service rescued two people trapped on rocks. Photo / supplied

“Thankfully they were unharmed, but it’s a timely reminder about how these situations can change in an instant.

Larsen said the location, changing tides and a lack of light can change everything very quickly.

“It’s now spring and the water is getting warmer and the evenings are getting lighter.

“What may seem like a safe area can become a dangerous and risky location faster than you might realise so we encourage everyone choosing to be in and around the water to have a safety plan in mind.”

Muriwai Volunteer Lifeguard Services search and rescue coordinator Glenn Gowthrope said a great response almost certainly saved the lives of the two young girls.

“The tide was halfway in, with just 45 minutes of daylight remaining. The spot they were standing would have been pounded by the 2.5m swell within about an hour, with no means of escape.”

Gowthorpe said, that due to the location, time available and swell, crews decided to climb around the rocks and wade through the surf instead of utilising a Rescue Water Craft.

“Our Search and Rescue squad did a fantastic job and got the job done and managed to retrieve the two girls safe and sound, just as the sun was setting.”

Fire and Emergency NZ (Fenz) sent three fire trucks, two support vehicles and a specialist lines rescue crew to the scene about 5.25pm.